drm/msm: a6xx: Fix improper u64 division

This patch uses the proper do_div() macro to perform u64 division and
guards against overflow if the result is too large for the unsigned long
return type

Fixes: a2c3c0a54d drm/msm/a6xx: Add devfreq support for a6xx
Cc: Sharat Masetty <smasetty@codeaurora.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>
This commit is contained in:
Sean Paul 2018-10-08 14:24:14 -04:00 committed by Rob Clark
parent 0f5427219b
commit 16f3710218
1 changed files with 7 additions and 4 deletions

View File

@ -761,18 +761,21 @@ static unsigned long a6xx_gpu_busy(struct msm_gpu *gpu)
{
struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
struct a6xx_gpu *a6xx_gpu = to_a6xx_gpu(adreno_gpu);
u64 busy_cycles;
unsigned long busy_time;
u64 busy_cycles, busy_time;
busy_cycles = gmu_read64(&a6xx_gpu->gmu,
REG_A6XX_GMU_CX_GMU_POWER_COUNTER_XOCLK_0_L,
REG_A6XX_GMU_CX_GMU_POWER_COUNTER_XOCLK_0_H);
busy_time = ((busy_cycles - gpu->devfreq.busy_cycles) * 10) / 192;
busy_time = (busy_cycles - gpu->devfreq.busy_cycles) * 10;
do_div(busy_time, 192);
gpu->devfreq.busy_cycles = busy_cycles;
return busy_time;
if (WARN_ON(busy_time > ~0LU))
return ~0LU;
return (unsigned long)busy_time;
}
static const struct adreno_gpu_funcs funcs = {